Continuous wood grinder of the chain type



R. T. LANG Feb. 2, 1932.

CONTINUOUS WOOD GRINDER OF THE CHAIN TYPE Filed July 2, 1926 Y HiYEZ/lU/i Way A TTORNE Y Patented Feb. 2, 1932 UNrrsn STATES PATENT OFFICE RICHARD T. LANG, OF wnnnewxnnnnw JERSEY, ASSIGNOR TO AMERICAN VOITH CONTACT (10., INC., 013 NEW,YORK, N. Y A CORPORATION OF NEW YORK oon'rrivuons woon eninnnn or THE CHAIN 'rxrn Application filed. July 2,

This invention relates to continuous wood grinders of the chain type and more p articularly has for its object to provide 1111- proved chain guiding means whereby the chain as it passes below the guiding walls of the magazine and enters the operative sphere of the lower sprocket, is positively guided by auxiliary guiding means a distance below the guiding means of said magazine and whilev being engaged by the lower sprocket. A further object is to maintain such positive support during all thetime that it is acted upon bythe lower sprocket and while the lower sprocket transmits its force against the charge in the magazine.

A further object of the invention is to provide a special construction of they chain links so that the forces exerted upon the links in respect to their rigidity may be transposed to the greatest extent to the charge within the magazine, said construction of chain links acting in the nature of an extension of the positively guided chain. For these pur:

poses the chain or chains areeiiectivelyand positively guided down to or closely adjacent to the horizontal center planeof the lower sprocket wheel so that no relaxation in the effective pack of the wood in the magazine can arise.

In the structures of continuous. wood grinders. of the chain type heretofore used the guides for the chain type only extend down to the top of the gap in the walls of the lower pocket of the magazine so that the chain links, after their supporting rollers or the like have left the guides, were forced outwardly by the thrust ofthe wood in the magazine. This, outward thrust of the chain by the wood in the magazine thereby extended the width of thewood charge in the magazine.- As. the result of this extension of the wood charge in a lateral direction, the force of the wood against the grindstone is reduced 3Illl3l1l1$ the eiiiciency of the wood grinder is. correspondingly decreased. lnsteadrof a desiredtantness, a laxity results. The effect of this widening out of the effective width of the magazinewas a loosening of the. grip of the links on the wood inthe. magazine at these. spots, which is-identicalw-ith the loos- 1926. Serial No. 120,005.

ening of the wood pack itself, followed by a recompressing after the roller in question has come in contact with the sprocket wheel. This continuous loosening and recompressing of the wood in the neighborhood of the stone has. a very unfavorable influence on the smooth fit of the wood to the stone and results in crushing the wood by the points of the chain links whereby jams in the magazine are created which cannot be overcome by the feed motor and which finally result in stalling the feed motor and-hence the feed of the wood to the stone. Another unfavorable result of the relaxing of the pull is a resetting of the logs in the neighborhood ofor on the stone, with consecutive production'of coarse pulp and slivers in the resetting period. These disadvantages are eliminated bybringing the guides for the chains down to the center plane of the lower sprocket to a position as close as possible thereto, thereby procuring a positive nonchanging grip ofthe chain on the wood and avoiding a loosening and recompressing of the pack. Theseactions are aided by the provision of specially shaped chain links with either a roller projecting on bothsidesover the teeth of the sprocket wheel, or links with a middle rollor having about the same width as the teeth of the sprocket. wheel and twov additional rollers outside. of the chain links. By bringing the guides down to the center'plane of the sprocket wheel as before pointed out, the gap above the sprocket wheel is only wide enough to let the teeth of the sprocket pass through,

whereas the projecting parts of the roller or the two additional rollers respectively are kept on the guide, thus avoiding any deflections of the chains from the straight downward trend.

The invention will be more fully described hereinafter, embodiments thereof shown in the drawings and the invention will be finally pointed out in the claims.

In the accompanying drawings,

Fig. l is a vertical cross-section through a part of the bottom pocket of the grinder magazine. I

Fig. 2 is partly avertical section through the sprocket wheel and partly a view looking in the direction towards the magazine.

Fig. 3 is a horizontal section on the line of the center of the lower sprocket wheel showing a roller chain with rollers projecting on both sides over the teeth of the. sprocket wheel, and

Fig. 4 is a section on the same line of another embodiment showing a roller chain with a middle roller and two additional rollers outside of the chain links but mounted on the same pin as the middle roller.

Similar characters of reference indicate corresponding parts throughout the various views.

Referring to the drawings, the lower side wall of the bottom pocket 10, which forms a part of the magazine has below the same a shaft 11 having the lower sprocket wheel 12 thereon which engages the rollers 13 of the chain 14. Below the sprocket 12 a curved guide wall 15 is provided in front of which is arranged a finger bar 16 which is in line with a wall 16-a forming the wall of the magazine. Below the finger bar 16 a grindstone 17 is arranged. In general, the parts just referred to are old and well known.

To the portion 10 of the side walls of the pocket there is secured a downwardly extended portion 20 which has its rearsurface 21, 22, shaped in such a way as to clear the hub 23 of the sprocket wheel 12. The curved part surface 22 of the rear surface extends to a point 24: which is substantially in line with the axis 25 of the shaft of the sprocket 12 and in front of this curved surface the member 20 has an auxiliary guide straight line portion 26 in line with the main guide straight front wall portion 27 of the pocket 10. The auxiliary guide 26 being in alignment'with the main guide 27,-acts as a continuation thereof so that the rollers 13 when passing along and beyond the main guide 27 and on to the extension 20 along its auxiliary guide 26 serve to support the rollers positively and effectively below the lowermost portion of the pocket 10 and up to a point in line with the axis 25 of the lower sprocket wheel. This extension 20 with its auxiliary guide 26 serves therefore to overcome the objections heretofore pointed out in the structures heretofore in use in which the rollers after passing below the main guide of the pocket 10 would move outwardly of the magazine and thereby widen the effective width of the magazine. The presence ofthis extension member 20 with its auxiliary guide 26 serves to maintain the links of t 1e chain in straight line fashion up to a point in line with the axis 25 of the shaft of the lower sprocket. The arrangement ofthis extension member 20 serves therefore a very useful function in that it maintains an equally effec tive width of the magazine to a pointvery close to the grinding surface of the grindstone.

A further departure from the known elements heretofore described is the provision of a novel chain link. This chain link 14 is provided with a downward angular extension 30 which serves to transmit any force exerted by the teeth of the sprocket wheel upon the roller of the chain in a downward angular inward direction towards the center part of the effective width of the magazine so that the links of the chain serve to press the wood charge 31 downwardly towards the grindstone and serve to compact the wood charge into a very eihcient position so that it may be efficiently operated upon by the grindstone. For this purpose the link 1% is provided with the extension 30 which has an operative surface 32 which is substantially at right angles to a line passing through the axis 33 of the roller 13. This is clearly shown in Figure 1 but the line there shown at right angles to surface 32 of the link may incline to a position between two rollers and in that case the operative surface 32 would be at a less angle to the horizontal. When the link 14 reaches its lowermost posi-v tion along the auxiliary guide 26 as indicated in Fig. 1 where a position is shown quite close to the very lowermost possible one, this line at right angles to the surface 32 and passing through the axis 33 meets the lowest point of the auxiliary guide 26 or the lowest point of the extension 20. Thereby the forces exerted by the sprocket 12 upon the roller 13 are transposed through the means of the downward extension 30 of the link to even a lower point than the lowestpoint of the auxiliary guide 26, and thereby the effective action of the auxiliary guide 26 is transposed I to a point below the axis 25 of the sprocket wheel 12.

It will further be noted that each link extension has an additional charge engaging surface 32 above the surface 32 and obliquely inclined at an obtuse angle with respect to the latter. This surface 32 acts to direct a wood block which may drop away from the surface 32 of the next higher link inwardly in respect to the magazine wall. 1 11 It will therefore, be apparent that since these surfaces 32 and 32 of the chain links bear a constant definite relation to the magazine wall and the wood charge laterally thereof during the feed travel of the chain, that the inward pressure on the charge and the downward feeding pressure will be uniformly transmitted to the entire mass of wood blocks throughout the effective length of the chain. Accordingly, it will be seen that by means of the present invention, the full capacity of the magazine is utilized at the face of the grinding stone which results in maximum production.

- In Figure 3 is shown an embodiment in which the single roller 13 projects on both sides of the teeth of the sprocket wheel 12,- and rests upon the auxiliary guide 26 at both protruding ends of the roller 13. The luricated pin or axle 32?), passes through the 13a are arranged outside of the side links 32-a. The central roller has about the width of the teeth of the sprocket and the lateraloutside rollers rest upon the auxiliary guide 26, thus avoiding any deflections of the chains from the downward trend.

Each link consists of the operative face 32 and side plates 32-00.

In Figure 2 is clearly seen a gap 38 in the side wall of the pocket providing sufficient space for the teeth of the sprocket to enter and pass therethrough.

I have shown various embodiments of my invention but changes may be made therein without departing from the spirit of the same as defined in the appending claims.

I claim: 7

1. A feed chain for wood pulp grinders comprising articulated links, each having laterally spaced walls provided with openings therein spaced longitudinally of the link to receive connecting pins and each of said walls at one of its ends having an oblique extension, and a wood charge engaging plate integrally connecting said oblique portions of the lateral walls of the link with each other. I

2. A feed chain link for wood pulp grinders having laterally spaced walls each provided with longitudinally spaced openings to receive link connecting pins, and each of said walls at one end having a longitudinal extension projecting in obliquely ofi'set relation from the longitudinal center line of the link and beyond one of said pin receiving openings, and a wood contacting plate integrally connecting said offset portions of the link walls with each other and substantially closing the side of the link having operative contact with the wood charge.

3. In a wood pulp grinder, a charge containin magazine, a feed chain mounted at one side of the'magazine for feeding the charge to a grinding stone at the lower end thereof, said chain comprising articulated links each connected with adjacent links by spaced transverse link pins, each of said links at one of its ends being formed with a charge feeding plate extending across the full width of the chain in substantially parallel relation to the aXis of an adjacent link pin, said plates of the chain links being in vertical alignment and in closely adj acent'relation to present a substantially continuous wood engaging surface ext-ending both vertically and transversely of the magazine.

4. In a wood pulp grinder, a charge containing magazine, a feed chain mounted at one side of the magazine for feeding the charge to a grinding stone at the lower end thereof, said chain comprising articulated links each connected with adjacent links by spaced transverse link pins, each of said links at one of its ends being formed with a charge feeding plate extending across the full width of the chain in substantially parallel relation to the axis of an adjacent link pin, said plates of the chain links being in vertical alignment and in closely adjacent relation to present a substantially continuous wood engaging surface extending both vertically and transversely of the magazine, each of said plates including a part disposed below the lower pin of the link obliquely inclined with respect to the horizontal and transmit ting thrust radially of the link pin upon the wood charge.

In testimony that I claim the foregoing as my invention, I have signed my name hereto.

RICHARD T. LANG. 

